VIVA 2011: 3-Year VIBRANT Results for Bare Stents and Stent Grafts in Long SFA Disease

October 18, 2011—Gary Ansel, MD, presented 3-year results from VIBRANT during a late-breaking clinical trial session at the VIVA 2011: Vascular Interventional Advances meeting in Las Vegas, Nevada. The VIBRANT study compared outcomes for treating complex superficial femoral artery (SFA) stenoses and occlusions using self-expanding stents with expanded polytetrafluoroethylene (ePTFE) lining (Viabahn endoprosthesis, Gore & Associates, Flagstaff, AZ) and without ePTFE lining (bare metal nitinol stent). 

Although recent studies have demonstrated the utility of bare nitinol stents and ePTFE-lined self-expanding stents in the percutaneous treatment of SFA occlusive disease, no previous prospective, randomized comparison of these two treatment modalities has been conducted.

In VIBRANT, 148 patients were enrolled across 14 sites in this multicenter, randomized clinical study. The average lesion length was 18 cm, with 59% of patients presenting with a chronic total occlusion. Duplex ultrasound follow-up occurred at 1, 6, 12, 24, and 36 months, with additional plain-film x-ray at the final three follow-up visits.

Dr. Ansel reported that the 30-day safety endpoint (a composite of major complications) revealed no difference between the two arms (P = .486). At the end of the 36-month follow-up window, there was no difference between the two arms with respect to primary patency or freedom from target lesion revascularization (P = .392 and P = .732, respectively).

The VIBRANT investigators also found that there were significantly more stent fractures in the bare nitinol stent arm (58%) versus the Viabahn endoprosthesis (4%; P < .001). The incidence of fracture for bare nitinol stents increased as lesion length increased. The pattern of restenosis was more commonly diffuse for bare nitinol stents versus focal edge stenosis for Viabahn. Both modalities showed significant clinical improvement versus baseline, and 85% of patients required one or more reintervention to maintain patency during the 36-month period.

According to Dr. Ansel, both stents and stent grafts showed durable 3-year clinical results in the treatment of long SFA occlusive disease. Stent fractures were significantly higher in the bare-metal stent arm of the study. No difference between the two groups with respect to primary patency was noted. The effects of heparin bonding and edge changes to Viabahn stent graft patency are pending.